This NCI K07 career development award application is designed to provide the applicant, Darren Mays, PhD, MPH, with the mentored experiences needed to become an independent investigator with expertise in behavioral tobacco control science relevant to tobacco regulatory policy. The proposed training and research activities are guided by a biobehavioral framework for tobacco-associated cancers and tobacco policy evaluation and will position me to gain new expertise in cross-cutting areas related to nicotine addiction, smoking cessation, and tobacco regulation. My career development will be guided by mentors with expertise in biobehavioral cancer and tobacco control science (Kenneth Tercyak, PhD; Raymond Niaura, PhD) and informed by an interdisciplinary team of expert consultants. Training activities will include didactic and applied skills components available through the unique resources of Georgetown University Medical Center, Georgetown Lombardi Comprehensive Cancer Center, Legacy's Schroeder Institute, and other local academic research institutions. The proposed research complements these career development activities by investigating the impact of graphic cigarette warning labels and plain (i.e., unbranded) cigarette packaging among young adult smokers ages 18-30. The 2009 Family Smoking Prevention and Tobacco Control Act was a critical step in U.S. tobacco control policy, requiring new graphic health warning labels to replace existing text-only warnings on cigarette packs. The Act also provides the framework to implement additional regulations on cigarette pack branding if evidence supports their use. Young adult smokers are a high priority group for this research area: they are vulnerable to tobacco industry promotions via cigarette packs and have a high risk of becoming addicted smokers, yet they are a sorely under-researched group. My training will help me design and execute behavioral research to address questions important to this tobacco control evidence base. The research component of this K07 complements my proposed training activities and will help to advance tobacco regulatory science by investigating the impact of warning message framing (gain- or loss-framed) and plain cigarette packaging for reducing the appeal of point-of-sale cigarette purchases (Aim 1) and the short-term prospective impact on smoking behaviors and motivation to quit (Aim 2), examining biobehavioral moderating and mediating mechanisms. Through prospective follow up, we will also assess the long-term durability of the impact of warning label message framing and plain packaging on smoking cessation to inform the development of a future R01 (Aim 3). By applying novel experimental methods, this study will generate data on the impact of cigarette packaging regulations on smoking behavior. This is a high priority research area for the NCI and the NIH collaborative Tobacco Regulatory Science Program. The experiences of this K07 will prepare me to pursue independent research focusing on behavioral tobacco control science and regulatory policy to prevent tobacco-associated cancers in the U.S.